1 files changed, 158 insertions, 91 deletions

diff --git a/src/egl/main/eglcontext.c b/src/egl/main/eglcontext.c
index ee4b1b59f5..d0c6b1b64c 100644
--- a/src/egl/main/eglcontext.c
+++ b/src/egl/main/eglcontext.c
@@ -5,7 +5,7 @@
 #include "eglcontext.h"
 #include "egldisplay.h"
 #include "egldriver.h"
-#include "eglglobals.h"
+#include "eglcurrent.h"
 #include "eglsurface.h"
 
 
@@ -58,20 +58,6 @@ _EGLContext *
 _eglCreateContext(_EGLDriver *drv, _EGLDisplay *dpy, _EGLConfig *conf,
                   _EGLContext *share_list, const EGLint *attrib_list)
 {
-#if 0 /* example code */
-   _EGLContext *context;
-
-   context = (_EGLContext *) calloc(1, sizeof(_EGLContext));
-   if (!context)
-      return NULL;
-
-   if (!_eglInitContext(drv, context, conf, attrib_list)) {
-      free(context);
-      return NULL;
-   }
-
-   return context;
-#endif
    return NULL;
 }
 
@@ -140,99 +126,169 @@ _eglQueryContext(_EGLDriver *drv, _EGLDisplay *dpy, _EGLContext *c,
 
 
 /**
- * Drivers will typically call this to do the error checking and
- * update the various flags.
- * Then, the driver will do its device-dependent Make-Current stuff.
+ * Bind the context to the surfaces.  Return the surfaces that are "orphaned".
+ * That is, when the context is not NULL, return the surfaces it previously
+ * bound to;  when the context is NULL, the same surfaces are returned.
  */
-EGLBoolean
-_eglMakeCurrent(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *draw,
-                _EGLSurface *read, _EGLContext *ctx)
+static void
+_eglBindContextToSurfaces(_EGLContext *ctx,
+                          _EGLSurface **draw, _EGLSurface **read)
+{
+   _EGLSurface *newDraw = *draw, *newRead = *read;
+
+   if (newDraw->CurrentContext)
+      newDraw->CurrentContext->DrawSurface = NULL;
+   newDraw->CurrentContext = ctx;
+
+   if (newRead->CurrentContext)
+      newRead->CurrentContext->ReadSurface = NULL;
+   newRead->CurrentContext = ctx;
+
+   if (ctx) {
+      *draw = ctx->DrawSurface;
+      ctx->DrawSurface = newDraw;
+
+      *read = ctx->ReadSurface;
+      ctx->ReadSurface = newRead;
+   }
+}
+
+
+/**
+ * Bind the context to the thread and return the previous context.
+ *
+ * Note that the context may be NULL.
+ */
+static _EGLContext *
+_eglBindContextToThread(_EGLContext *ctx, _EGLThreadInfo *t)
 {
-   _EGLThreadInfo *t = _eglGetCurrentThread();
-   _EGLContext *oldContext = NULL;
-   _EGLSurface *oldDrawSurface = NULL;
-   _EGLSurface *oldReadSurface = NULL;
    EGLint apiIndex;
+   _EGLContext *oldCtx;
+
+   apiIndex = (ctx) ?
+      _eglConvertApiToIndex(ctx->ClientAPI) : t->CurrentAPIIndex;
+
+   oldCtx = t->CurrentContexts[apiIndex];
+   if (ctx == oldCtx)
+      return NULL;
+
+   if (oldCtx)
+      oldCtx->Binding = NULL;
+   if (ctx)
+      ctx->Binding = t;
+
+   t->CurrentContexts[apiIndex] = ctx;
+
+   return oldCtx;
+}
+
+
+/**
+ * Return true if the given context and surfaces can be made current.
+ */
+static EGLBoolean
+_eglCheckMakeCurrent(_EGLContext *ctx, _EGLSurface *draw, _EGLSurface *read)
+{
+   _EGLThreadInfo *t = _eglGetCurrentThread();
+   EGLint conflict_api;
 
    if (_eglIsCurrentThreadDummy())
       return _eglError(EGL_BAD_ALLOC, "eglMakeCurrent");
 
-   if (ctx) {
-      /* error checking */
-      if (ctx->Binding && ctx->Binding != t)
-         return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
-      if (draw == NULL || read == NULL)
-         return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
-      if (draw->Config != ctx->Config || read->Config != ctx->Config)
+   /* this is easy */
+   if (!ctx) {
+      if (draw || read)
          return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
-      if ((draw->Binding && draw->Binding->Binding != t) ||
-          (read->Binding && read->Binding->Binding != t))
-         return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
+      return EGL_TRUE;
+   }
+
+   /* ctx/draw/read must be all given */
+   if (draw == NULL || read == NULL)
+      return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
+
+   /* context stealing from another thread is not allowed */
+   if (ctx->Binding && ctx->Binding != t)
+      return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
+
+   /*
+    * The spec says
+    *
+    * "If ctx is current to some other thread, or if either draw or read are
+    * bound to contexts in another thread, an EGL_BAD_ACCESS error is
+    * generated."
+    *
+    * But it also says
+    *
+    * "at most one context may be bound to a particular surface at a given
+    * time"
+    *
+    * The latter is more restrictive so we can check only the latter case.
+    */
+   if ((draw->CurrentContext && draw->CurrentContext != ctx) ||
+       (read->CurrentContext && read->CurrentContext != ctx))
+      return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
 
+   /* simply require the configs to be equal */
+   if (draw->Config != ctx->Config || read->Config != ctx->Config)
+      return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
+
+   switch (ctx->ClientAPI) {
 #ifdef EGL_VERSION_1_4
-      /* OpenGL and OpenGL ES are conflicting */
-      switch (ctx->ClientAPI) {
-      case EGL_OPENGL_ES_API:
-         if (t->CurrentContexts[_eglConvertApiToIndex(EGL_OPENGL_API)])
-            return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
-         break;
-      case EGL_OPENGL_API:
-         if (t->CurrentContexts[_eglConvertApiToIndex(EGL_OPENGL_ES_API)])
-            return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
-         break;
-      default:
-         break;
-      }
+   /* OpenGL and OpenGL ES are conflicting */
+   case EGL_OPENGL_ES_API:
+      conflict_api = EGL_OPENGL_API;
+      break;
+   case EGL_OPENGL_API:
+      conflict_api = EGL_OPENGL_ES_API;
+      break;
 #endif
-      apiIndex = _eglConvertApiToIndex(ctx->ClientAPI);
-   }
-   else {
-      if (draw != NULL || read != NULL)
-         return _eglError(EGL_BAD_MATCH, "eglMakeCurrent");
-      apiIndex = t->CurrentAPIIndex;
+   default:
+      conflict_api = -1;
+      break;
    }
 
-   oldContext = t->CurrentContexts[apiIndex];
-   if (oldContext) {
-      oldDrawSurface = oldContext->DrawSurface;
-      oldReadSurface = oldContext->ReadSurface;
-      assert(oldDrawSurface);
-      assert(oldReadSurface);
-
-      /* break old bindings */
-      t->CurrentContexts[apiIndex] = NULL;
-      oldContext->Binding = NULL;
-      oldContext->DrawSurface = NULL;
-      oldContext->ReadSurface = NULL;
-      oldDrawSurface->Binding = NULL;
-      oldReadSurface->Binding = NULL;
+   if (conflict_api >= 0 && _eglGetAPIContext(conflict_api))
+      return _eglError(EGL_BAD_ACCESS, "eglMakeCurrent");
+
+   return EGL_TRUE;
+}
+
+
+/**
+ * Bind the context to the current thread and given surfaces.  Return the
+ * previously bound context and the surfaces it bound to.  Each argument is
+ * both input and output.
+ */
+EGLBoolean
+_eglBindContext(_EGLContext **ctx, _EGLSurface **draw, _EGLSurface **read)
+{
+   _EGLThreadInfo *t = _eglGetCurrentThread();
+   _EGLContext *newCtx = *ctx, *oldCtx;
+
+   if (!_eglCheckMakeCurrent(newCtx, *draw, *read))
+      return EGL_FALSE;
+
+   /* bind the new context */
+   oldCtx = _eglBindContextToThread(newCtx, t);
+   *ctx = oldCtx;
+   if (newCtx)
+      _eglBindContextToSurfaces(newCtx, draw, read);
 
+   /* unbind the old context from its binding surfaces */
+   if (oldCtx) {
       /*
-       * check if the old context or surfaces need to be deleted
+       * If the new context replaces some old context, the new one should not
+       * be current before the replacement and it should not be bound to any
+       * surface.
        */
-      if (!_eglIsSurfaceLinked(oldDrawSurface)) {
-         assert(draw != oldDrawSurface && read != oldDrawSurface);
-         drv->API.DestroySurface(drv, dpy, oldDrawSurface);
-      }
-      if (oldReadSurface != oldDrawSurface &&
-          !_eglIsSurfaceLinked(oldReadSurface)) {
-         assert(draw != oldReadSurface && read != oldReadSurface);
-         drv->API.DestroySurface(drv, dpy, oldReadSurface);
-      }
-      if (!_eglIsContextLinked(oldContext)) {
-         assert(ctx != oldContext);
-         drv->API.DestroyContext(drv, dpy, oldContext);
-      }
-   }
+      if (newCtx)
+         assert(!*draw && !*read);
 
-   /* build new bindings */
-   if (ctx) {
-      t->CurrentContexts[apiIndex] = ctx;
-      ctx->Binding = t;
-      ctx->DrawSurface = draw;
-      ctx->ReadSurface = read;
-      draw->Binding = ctx;
-      read->Binding = ctx;
+      *draw = oldCtx->DrawSurface;
+      *read = oldCtx->ReadSurface;
+      assert(*draw && *read);
+
+      _eglBindContextToSurfaces(NULL, draw, read);
    }
 
    return EGL_TRUE;
@@ -240,6 +296,17 @@ _eglMakeCurrent(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *draw,
 
 
 /**
+ * Just a placeholder/demo function.  Drivers should override this.
+ */
+EGLBoolean
+_eglMakeCurrent(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *draw,
+                _EGLSurface *read, _EGLContext *ctx)
+{
+   return EGL_FALSE;
+}
+
+
+/**
  * This is defined by the EGL_MESA_copy_context extension.
  */
 EGLBoolean